Holmgren, N. (1942)
Studies of the head in fishes. Part 3. The phylogeny of elasmobranch fishes. Acta Zoologica(Stockholm), 23(1–3), 129–261
DOI: 10.1111/j.1463-6395.1942.tb00012.x
Holmgren, N. (1941)
Studies on the head in fishes. Embryological, morphological, and phylogenetical researches. Part II. Comparative anatomy of the adult selachian skull, with remarks on the dorsal fins in sharks. Acta Zoologica(Stockholm), 22(1–3), 1–100
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Holmgren, N. (1940)
Studies on the head in fishes. Embryological, morphological, and phylogenetical researches. Part I. Development of the skull in sharks and rays. Acta Zoologica(Stockholm), 21(1–3), 51–267
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